One of the most remarkable caves in all of Iceland was created by a once raging river of lava.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

Surrounded by ash fields in Iceland, an impossibly verdant valley looks like something out of a fairytale.

This mountain fissure hides a secret path to a secluded mossy grotto within the rock itself.

The oldest church in Iceland is one of the few to feature ornate decoration.

The most powerful waterfall in all of Europe.

Climb right into the heart of this colorful Iceland volcano.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

The youngest volcano in Central America.

Located in the mountains of Nicaragua, one man has spent most of life beautifying a massive cliff by hand.

The tunnel's elegant proportions keep you snug with no claustrophobia freak-out.

Countless grotesque faces stare out from this eerie Prague art wall.

A Jenga-style cylindrical tower of books that appears to go on forever.

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

Started as a kitchen garden, now the second largest botanical garden in the world.

This bakery and museum offers tours of the tastes and mythology of Aachen's signature spice biscuit—just don't ask for the recipe.

A micronation on an islet along the coast of a Portuguese island.

Men in rubber-soled boots serve as your "brakes" on this toboggan ride Hemingway described as "exhilarating."

Iron Age runes and ruins hide in plain sight along this Portuguese beach.

As the highest point in the Mid-Atlantic range this stratovolcano offers spectacular views.

Rainwater transformed this old quarry into a peaceful pond you won't find in most tourist books.

You can cross from one country to another in a single hop on this little bridge.

One of the smallest bookstores on the planet.